The equation would be
x - 18 = collection left
X = how much was your collection before you gave your brother 13 cards
Since we don't know how big was your collection before, this would be the equation to solve it.
Answer:
Step-by-step explanation:
the shape looks like a cube.. and maybe they say something about that outside of the picture, even but assuming that it is a cube, we know all the sides are the same.
we also know that the area of one side of the cube is 3 
so multiply that
W x L = area
3
* 3
= area
10
= area
10.5625 = area
those two answer above are the same .. just one is in fractions and one is in decimals
there are 6 sides on a cube, so multiply the above answer by 6
6* answer = 63.375
63
( this is your answer)
both of those are also identical , but look different for the reasons I mentioned above
use which ever from seems better to you. :)
(10 1/2)/(3/8)
= (21/2)/(3/8) Convert to improper
= (21/2)*(8/3) Multiply by reciprocal of second
=(7/1)*(4/1) Cross reduce
=28 Multiply
5a)
2x + 94 = 7x + 49 (vertical angles are equal)
2x - 7x = -94 + 49
-5x = -45
x = 9
Answer
9
5b)
4y + 7x + 49 = 180 (supplementary angles, sum = 180)
4y + 7(9) + 49 = 180
4y + 112 = 180
4y = 68
y = 17
Answer
17
6)
x = 6x - 290 (vertical angles are equal)
-5x = -290
x = 58
Answer
58
I would say the best option is A.HL